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<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<span class="sourceLineNo">003</span> * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<span class="sourceLineNo">004</span> * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<span class="sourceLineNo">005</span> * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<span class="sourceLineNo">006</span> * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<span class="sourceLineNo">007</span> * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<span class="sourceLineNo">008</span> *<a name="line.8"></a>
<span class="sourceLineNo">009</span> *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<span class="sourceLineNo">010</span> *<a name="line.10"></a>
<span class="sourceLineNo">011</span> * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<span class="sourceLineNo">012</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<span class="sourceLineNo">013</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<span class="sourceLineNo">014</span> * See the License for the specific language governing permissions and<a name="line.14"></a>
<span class="sourceLineNo">015</span> * limitations under the License.<a name="line.15"></a>
<span class="sourceLineNo">016</span> */<a name="line.16"></a>
<span class="sourceLineNo">017</span><a name="line.17"></a>
<span class="sourceLineNo">018</span>package org.apache.commons.logging.impl;<a name="line.18"></a>
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>import java.io.PrintWriter;<a name="line.20"></a>
<span class="sourceLineNo">021</span>import java.io.StringWriter;<a name="line.21"></a>
<span class="sourceLineNo">022</span>import java.lang.reflect.Constructor;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import java.lang.reflect.InvocationTargetException;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import java.lang.reflect.Method;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import java.net.URL;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import java.security.AccessController;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import java.security.PrivilegedAction;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import java.util.Hashtable;<a name="line.28"></a>
<span class="sourceLineNo">029</span><a name="line.29"></a>
<span class="sourceLineNo">030</span>import org.apache.commons.logging.Log;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import org.apache.commons.logging.LogConfigurationException;<a name="line.31"></a>
<span class="sourceLineNo">032</span>import org.apache.commons.logging.LogFactory;<a name="line.32"></a>
<span class="sourceLineNo">033</span><a name="line.33"></a>
<span class="sourceLineNo">034</span>/**<a name="line.34"></a>
<span class="sourceLineNo">035</span> * Concrete subclass of {@link LogFactory} that implements the<a name="line.35"></a>
<span class="sourceLineNo">036</span> * following algorithm to dynamically select a logging implementation<a name="line.36"></a>
<span class="sourceLineNo">037</span> * class to instantiate a wrapper for:<a name="line.37"></a>
<span class="sourceLineNo">038</span> * &lt;ul&gt;<a name="line.38"></a>
<span class="sourceLineNo">039</span> * &lt;li&gt;Use a factory configuration attribute named<a name="line.39"></a>
<span class="sourceLineNo">040</span> *     &lt;code&gt;org.apache.commons.logging.Log&lt;/code&gt; to identify the<a name="line.40"></a>
<span class="sourceLineNo">041</span> *     requested implementation class.&lt;/li&gt;<a name="line.41"></a>
<span class="sourceLineNo">042</span> * &lt;li&gt;Use the &lt;code&gt;org.apache.commons.logging.Log&lt;/code&gt; system property<a name="line.42"></a>
<span class="sourceLineNo">043</span> *     to identify the requested implementation class.&lt;/li&gt;<a name="line.43"></a>
<span class="sourceLineNo">044</span> * &lt;li&gt;If &lt;em&gt;Log4J&lt;/em&gt; is available, return an instance of<a name="line.44"></a>
<span class="sourceLineNo">045</span> *     &lt;code&gt;org.apache.commons.logging.impl.Log4JLogger&lt;/code&gt;.&lt;/li&gt;<a name="line.45"></a>
<span class="sourceLineNo">046</span> * &lt;li&gt;If &lt;em&gt;JDK 1.4 or later&lt;/em&gt; is available, return an instance of<a name="line.46"></a>
<span class="sourceLineNo">047</span> *     &lt;code&gt;org.apache.commons.logging.impl.Jdk14Logger&lt;/code&gt;.&lt;/li&gt;<a name="line.47"></a>
<span class="sourceLineNo">048</span> * &lt;li&gt;Otherwise, return an instance of<a name="line.48"></a>
<span class="sourceLineNo">049</span> *     &lt;code&gt;org.apache.commons.logging.impl.SimpleLog&lt;/code&gt;.&lt;/li&gt;<a name="line.49"></a>
<span class="sourceLineNo">050</span> * &lt;/ul&gt;<a name="line.50"></a>
<span class="sourceLineNo">051</span> * &lt;p&gt;<a name="line.51"></a>
<span class="sourceLineNo">052</span> * If the selected {@link Log} implementation class has a<a name="line.52"></a>
<span class="sourceLineNo">053</span> * &lt;code&gt;setLogFactory()&lt;/code&gt; method that accepts a {@link LogFactory}<a name="line.53"></a>
<span class="sourceLineNo">054</span> * parameter, this method will be called on each newly created instance<a name="line.54"></a>
<span class="sourceLineNo">055</span> * to identify the associated factory.  This makes factory configuration<a name="line.55"></a>
<span class="sourceLineNo">056</span> * attributes available to the Log instance, if it so desires.<a name="line.56"></a>
<span class="sourceLineNo">057</span> * &lt;p&gt;<a name="line.57"></a>
<span class="sourceLineNo">058</span> * This factory will remember previously created &lt;code&gt;Log&lt;/code&gt; instances<a name="line.58"></a>
<span class="sourceLineNo">059</span> * for the same name, and will return them on repeated requests to the<a name="line.59"></a>
<span class="sourceLineNo">060</span> * &lt;code&gt;getInstance()&lt;/code&gt; method.<a name="line.60"></a>
<span class="sourceLineNo">061</span> *<a name="line.61"></a>
<span class="sourceLineNo">062</span> * @version $Id: LogFactoryImpl.java 1449064 2013-02-22 14:49:22Z tn $<a name="line.62"></a>
<span class="sourceLineNo">063</span> */<a name="line.63"></a>
<span class="sourceLineNo">064</span>public class LogFactoryImpl extends LogFactory {<a name="line.64"></a>
<span class="sourceLineNo">065</span><a name="line.65"></a>
<span class="sourceLineNo">066</span>    /** Log4JLogger class name */<a name="line.66"></a>
<span class="sourceLineNo">067</span>    private static final String LOGGING_IMPL_LOG4J_LOGGER = "org.apache.commons.logging.impl.Log4JLogger";<a name="line.67"></a>
<span class="sourceLineNo">068</span>    /** Jdk14Logger class name */<a name="line.68"></a>
<span class="sourceLineNo">069</span>    private static final String LOGGING_IMPL_JDK14_LOGGER = "org.apache.commons.logging.impl.Jdk14Logger";<a name="line.69"></a>
<span class="sourceLineNo">070</span>    /** Jdk13LumberjackLogger class name */<a name="line.70"></a>
<span class="sourceLineNo">071</span>    private static final String LOGGING_IMPL_LUMBERJACK_LOGGER =<a name="line.71"></a>
<span class="sourceLineNo">072</span>            "org.apache.commons.logging.impl.Jdk13LumberjackLogger";<a name="line.72"></a>
<span class="sourceLineNo">073</span><a name="line.73"></a>
<span class="sourceLineNo">074</span>    /** SimpleLog class name */<a name="line.74"></a>
<span class="sourceLineNo">075</span>    private static final String LOGGING_IMPL_SIMPLE_LOGGER = "org.apache.commons.logging.impl.SimpleLog";<a name="line.75"></a>
<span class="sourceLineNo">076</span><a name="line.76"></a>
<span class="sourceLineNo">077</span>    private static final String PKG_IMPL="org.apache.commons.logging.impl.";<a name="line.77"></a>
<span class="sourceLineNo">078</span>    private static final int PKG_LEN = PKG_IMPL.length();<a name="line.78"></a>
<span class="sourceLineNo">079</span><a name="line.79"></a>
<span class="sourceLineNo">080</span>    // ----------------------------------------------------------- Constructors<a name="line.80"></a>
<span class="sourceLineNo">081</span><a name="line.81"></a>
<span class="sourceLineNo">082</span>    /**<a name="line.82"></a>
<span class="sourceLineNo">083</span>     * Public no-arguments constructor required by the lookup mechanism.<a name="line.83"></a>
<span class="sourceLineNo">084</span>     */<a name="line.84"></a>
<span class="sourceLineNo">085</span>    public LogFactoryImpl() {<a name="line.85"></a>
<span class="sourceLineNo">086</span>        super();<a name="line.86"></a>
<span class="sourceLineNo">087</span>        initDiagnostics();  // method on this object<a name="line.87"></a>
<span class="sourceLineNo">088</span>        if (isDiagnosticsEnabled()) {<a name="line.88"></a>
<span class="sourceLineNo">089</span>            logDiagnostic("Instance created.");<a name="line.89"></a>
<span class="sourceLineNo">090</span>        }<a name="line.90"></a>
<span class="sourceLineNo">091</span>    }<a name="line.91"></a>
<span class="sourceLineNo">092</span><a name="line.92"></a>
<span class="sourceLineNo">093</span>    // ----------------------------------------------------- Manifest Constants<a name="line.93"></a>
<span class="sourceLineNo">094</span><a name="line.94"></a>
<span class="sourceLineNo">095</span>    /**<a name="line.95"></a>
<span class="sourceLineNo">096</span>     * The name (&lt;code&gt;org.apache.commons.logging.Log&lt;/code&gt;) of the system<a name="line.96"></a>
<span class="sourceLineNo">097</span>     * property identifying our {@link Log} implementation class.<a name="line.97"></a>
<span class="sourceLineNo">098</span>     */<a name="line.98"></a>
<span class="sourceLineNo">099</span>    public static final String LOG_PROPERTY = "org.apache.commons.logging.Log";<a name="line.99"></a>
<span class="sourceLineNo">100</span><a name="line.100"></a>
<span class="sourceLineNo">101</span>    /**<a name="line.101"></a>
<span class="sourceLineNo">102</span>     * The deprecated system property used for backwards compatibility with<a name="line.102"></a>
<span class="sourceLineNo">103</span>     * old versions of JCL.<a name="line.103"></a>
<span class="sourceLineNo">104</span>     */<a name="line.104"></a>
<span class="sourceLineNo">105</span>    protected static final String LOG_PROPERTY_OLD = "org.apache.commons.logging.log";<a name="line.105"></a>
<span class="sourceLineNo">106</span><a name="line.106"></a>
<span class="sourceLineNo">107</span>    /**<a name="line.107"></a>
<span class="sourceLineNo">108</span>     * The name (&lt;code&gt;org.apache.commons.logging.Log.allowFlawedContext&lt;/code&gt;)<a name="line.108"></a>
<span class="sourceLineNo">109</span>     * of the system property which can be set true/false to<a name="line.109"></a>
<span class="sourceLineNo">110</span>     * determine system behaviour when a bad context-classloader is encountered.<a name="line.110"></a>
<span class="sourceLineNo">111</span>     * When set to false, a LogConfigurationException is thrown if<a name="line.111"></a>
<span class="sourceLineNo">112</span>     * LogFactoryImpl is loaded via a child classloader of the TCCL (this<a name="line.112"></a>
<span class="sourceLineNo">113</span>     * should never happen in sane systems).<a name="line.113"></a>
<span class="sourceLineNo">114</span>     *<a name="line.114"></a>
<span class="sourceLineNo">115</span>     * Default behaviour: true (tolerates bad context classloaders)<a name="line.115"></a>
<span class="sourceLineNo">116</span>     *<a name="line.116"></a>
<span class="sourceLineNo">117</span>     * See also method setAttribute.<a name="line.117"></a>
<span class="sourceLineNo">118</span>     */<a name="line.118"></a>
<span class="sourceLineNo">119</span>    public static final String ALLOW_FLAWED_CONTEXT_PROPERTY =<a name="line.119"></a>
<span class="sourceLineNo">120</span>        "org.apache.commons.logging.Log.allowFlawedContext";<a name="line.120"></a>
<span class="sourceLineNo">121</span><a name="line.121"></a>
<span class="sourceLineNo">122</span>    /**<a name="line.122"></a>
<span class="sourceLineNo">123</span>     * The name (&lt;code&gt;org.apache.commons.logging.Log.allowFlawedDiscovery&lt;/code&gt;)<a name="line.123"></a>
<span class="sourceLineNo">124</span>     * of the system property which can be set true/false to<a name="line.124"></a>
<span class="sourceLineNo">125</span>     * determine system behaviour when a bad logging adapter class is<a name="line.125"></a>
<span class="sourceLineNo">126</span>     * encountered during logging discovery. When set to false, an<a name="line.126"></a>
<span class="sourceLineNo">127</span>     * exception will be thrown and the app will fail to start. When set<a name="line.127"></a>
<span class="sourceLineNo">128</span>     * to true, discovery will continue (though the user might end up<a name="line.128"></a>
<span class="sourceLineNo">129</span>     * with a different logging implementation than they expected).<a name="line.129"></a>
<span class="sourceLineNo">130</span>     * &lt;p&gt;<a name="line.130"></a>
<span class="sourceLineNo">131</span>     * Default behaviour: true (tolerates bad logging adapters)<a name="line.131"></a>
<span class="sourceLineNo">132</span>     *<a name="line.132"></a>
<span class="sourceLineNo">133</span>     * See also method setAttribute.<a name="line.133"></a>
<span class="sourceLineNo">134</span>     */<a name="line.134"></a>
<span class="sourceLineNo">135</span>    public static final String ALLOW_FLAWED_DISCOVERY_PROPERTY =<a name="line.135"></a>
<span class="sourceLineNo">136</span>        "org.apache.commons.logging.Log.allowFlawedDiscovery";<a name="line.136"></a>
<span class="sourceLineNo">137</span><a name="line.137"></a>
<span class="sourceLineNo">138</span>    /**<a name="line.138"></a>
<span class="sourceLineNo">139</span>     * The name (&lt;code&gt;org.apache.commons.logging.Log.allowFlawedHierarchy&lt;/code&gt;)<a name="line.139"></a>
<span class="sourceLineNo">140</span>     * of the system property which can be set true/false to<a name="line.140"></a>
<span class="sourceLineNo">141</span>     * determine system behaviour when a logging adapter class is<a name="line.141"></a>
<span class="sourceLineNo">142</span>     * encountered which has bound to the wrong Log class implementation.<a name="line.142"></a>
<span class="sourceLineNo">143</span>     * When set to false, an exception will be thrown and the app will fail<a name="line.143"></a>
<span class="sourceLineNo">144</span>     * to start. When set to true, discovery will continue (though the user<a name="line.144"></a>
<span class="sourceLineNo">145</span>     * might end up with a different logging implementation than they expected).<a name="line.145"></a>
<span class="sourceLineNo">146</span>     * &lt;p&gt;<a name="line.146"></a>
<span class="sourceLineNo">147</span>     * Default behaviour: true (tolerates bad Log class hierarchy)<a name="line.147"></a>
<span class="sourceLineNo">148</span>     *<a name="line.148"></a>
<span class="sourceLineNo">149</span>     * See also method setAttribute.<a name="line.149"></a>
<span class="sourceLineNo">150</span>     */<a name="line.150"></a>
<span class="sourceLineNo">151</span>    public static final String ALLOW_FLAWED_HIERARCHY_PROPERTY =<a name="line.151"></a>
<span class="sourceLineNo">152</span>        "org.apache.commons.logging.Log.allowFlawedHierarchy";<a name="line.152"></a>
<span class="sourceLineNo">153</span><a name="line.153"></a>
<span class="sourceLineNo">154</span>    /**<a name="line.154"></a>
<span class="sourceLineNo">155</span>     * The names of classes that will be tried (in order) as logging<a name="line.155"></a>
<span class="sourceLineNo">156</span>     * adapters. Each class is expected to implement the Log interface,<a name="line.156"></a>
<span class="sourceLineNo">157</span>     * and to throw NoClassDefFound or ExceptionInInitializerError when<a name="line.157"></a>
<span class="sourceLineNo">158</span>     * loaded if the underlying logging library is not available. Any<a name="line.158"></a>
<span class="sourceLineNo">159</span>     * other error indicates that the underlying logging library is available<a name="line.159"></a>
<span class="sourceLineNo">160</span>     * but broken/unusable for some reason.<a name="line.160"></a>
<span class="sourceLineNo">161</span>     */<a name="line.161"></a>
<span class="sourceLineNo">162</span>    private static final String[] classesToDiscover = {<a name="line.162"></a>
<span class="sourceLineNo">163</span>            LOGGING_IMPL_LOG4J_LOGGER,<a name="line.163"></a>
<span class="sourceLineNo">164</span>            "org.apache.commons.logging.impl.Jdk14Logger",<a name="line.164"></a>
<span class="sourceLineNo">165</span>            "org.apache.commons.logging.impl.Jdk13LumberjackLogger",<a name="line.165"></a>
<span class="sourceLineNo">166</span>            "org.apache.commons.logging.impl.SimpleLog"<a name="line.166"></a>
<span class="sourceLineNo">167</span>    };<a name="line.167"></a>
<span class="sourceLineNo">168</span><a name="line.168"></a>
<span class="sourceLineNo">169</span>    // ----------------------------------------------------- Instance Variables<a name="line.169"></a>
<span class="sourceLineNo">170</span><a name="line.170"></a>
<span class="sourceLineNo">171</span>    /**<a name="line.171"></a>
<span class="sourceLineNo">172</span>     * Determines whether logging classes should be loaded using the thread-context<a name="line.172"></a>
<span class="sourceLineNo">173</span>     * classloader, or via the classloader that loaded this LogFactoryImpl class.<a name="line.173"></a>
<span class="sourceLineNo">174</span>     */<a name="line.174"></a>
<span class="sourceLineNo">175</span>    private boolean useTCCL = true;<a name="line.175"></a>
<span class="sourceLineNo">176</span><a name="line.176"></a>
<span class="sourceLineNo">177</span>    /**<a name="line.177"></a>
<span class="sourceLineNo">178</span>     * The string prefixed to every message output by the logDiagnostic method.<a name="line.178"></a>
<span class="sourceLineNo">179</span>     */<a name="line.179"></a>
<span class="sourceLineNo">180</span>    private String diagnosticPrefix;<a name="line.180"></a>
<span class="sourceLineNo">181</span><a name="line.181"></a>
<span class="sourceLineNo">182</span>    /**<a name="line.182"></a>
<span class="sourceLineNo">183</span>     * Configuration attributes.<a name="line.183"></a>
<span class="sourceLineNo">184</span>     */<a name="line.184"></a>
<span class="sourceLineNo">185</span>    protected Hashtable attributes = new Hashtable();<a name="line.185"></a>
<span class="sourceLineNo">186</span><a name="line.186"></a>
<span class="sourceLineNo">187</span>    /**<a name="line.187"></a>
<span class="sourceLineNo">188</span>     * The {@link org.apache.commons.logging.Log} instances that have<a name="line.188"></a>
<span class="sourceLineNo">189</span>     * already been created, keyed by logger name.<a name="line.189"></a>
<span class="sourceLineNo">190</span>     */<a name="line.190"></a>
<span class="sourceLineNo">191</span>    protected Hashtable instances = new Hashtable();<a name="line.191"></a>
<span class="sourceLineNo">192</span><a name="line.192"></a>
<span class="sourceLineNo">193</span>    /**<a name="line.193"></a>
<span class="sourceLineNo">194</span>     * Name of the class implementing the Log interface.<a name="line.194"></a>
<span class="sourceLineNo">195</span>     */<a name="line.195"></a>
<span class="sourceLineNo">196</span>    private String logClassName;<a name="line.196"></a>
<span class="sourceLineNo">197</span><a name="line.197"></a>
<span class="sourceLineNo">198</span>    /**<a name="line.198"></a>
<span class="sourceLineNo">199</span>     * The one-argument constructor of the<a name="line.199"></a>
<span class="sourceLineNo">200</span>     * {@link org.apache.commons.logging.Log}<a name="line.200"></a>
<span class="sourceLineNo">201</span>     * implementation class that will be used to create new instances.<a name="line.201"></a>
<span class="sourceLineNo">202</span>     * This value is initialized by &lt;code&gt;getLogConstructor()&lt;/code&gt;,<a name="line.202"></a>
<span class="sourceLineNo">203</span>     * and then returned repeatedly.<a name="line.203"></a>
<span class="sourceLineNo">204</span>     */<a name="line.204"></a>
<span class="sourceLineNo">205</span>    protected Constructor logConstructor = null;<a name="line.205"></a>
<span class="sourceLineNo">206</span><a name="line.206"></a>
<span class="sourceLineNo">207</span>    /**<a name="line.207"></a>
<span class="sourceLineNo">208</span>     * The signature of the Constructor to be used.<a name="line.208"></a>
<span class="sourceLineNo">209</span>     */<a name="line.209"></a>
<span class="sourceLineNo">210</span>    protected Class logConstructorSignature[] = { java.lang.String.class };<a name="line.210"></a>
<span class="sourceLineNo">211</span><a name="line.211"></a>
<span class="sourceLineNo">212</span>    /**<a name="line.212"></a>
<span class="sourceLineNo">213</span>     * The one-argument &lt;code&gt;setLogFactory&lt;/code&gt; method of the selected<a name="line.213"></a>
<span class="sourceLineNo">214</span>     * {@link org.apache.commons.logging.Log} method, if it exists.<a name="line.214"></a>
<span class="sourceLineNo">215</span>     */<a name="line.215"></a>
<span class="sourceLineNo">216</span>    protected Method logMethod = null;<a name="line.216"></a>
<span class="sourceLineNo">217</span><a name="line.217"></a>
<span class="sourceLineNo">218</span>    /**<a name="line.218"></a>
<span class="sourceLineNo">219</span>     * The signature of the &lt;code&gt;setLogFactory&lt;/code&gt; method to be used.<a name="line.219"></a>
<span class="sourceLineNo">220</span>     */<a name="line.220"></a>
<span class="sourceLineNo">221</span>    protected Class logMethodSignature[] = { LogFactory.class };<a name="line.221"></a>
<span class="sourceLineNo">222</span><a name="line.222"></a>
<span class="sourceLineNo">223</span>    /**<a name="line.223"></a>
<span class="sourceLineNo">224</span>     * See getBaseClassLoader and initConfiguration.<a name="line.224"></a>
<span class="sourceLineNo">225</span>     */<a name="line.225"></a>
<span class="sourceLineNo">226</span>    private boolean allowFlawedContext;<a name="line.226"></a>
<span class="sourceLineNo">227</span><a name="line.227"></a>
<span class="sourceLineNo">228</span>    /**<a name="line.228"></a>
<span class="sourceLineNo">229</span>     * See handleFlawedDiscovery and initConfiguration.<a name="line.229"></a>
<span class="sourceLineNo">230</span>     */<a name="line.230"></a>
<span class="sourceLineNo">231</span>    private boolean allowFlawedDiscovery;<a name="line.231"></a>
<span class="sourceLineNo">232</span><a name="line.232"></a>
<span class="sourceLineNo">233</span>    /**<a name="line.233"></a>
<span class="sourceLineNo">234</span>     * See handleFlawedHierarchy and initConfiguration.<a name="line.234"></a>
<span class="sourceLineNo">235</span>     */<a name="line.235"></a>
<span class="sourceLineNo">236</span>    private boolean allowFlawedHierarchy;<a name="line.236"></a>
<span class="sourceLineNo">237</span><a name="line.237"></a>
<span class="sourceLineNo">238</span>    // --------------------------------------------------------- Public Methods<a name="line.238"></a>
<span class="sourceLineNo">239</span><a name="line.239"></a>
<span class="sourceLineNo">240</span>    /**<a name="line.240"></a>
<span class="sourceLineNo">241</span>     * Return the configuration attribute with the specified name (if any),<a name="line.241"></a>
<span class="sourceLineNo">242</span>     * or &lt;code&gt;null&lt;/code&gt; if there is no such attribute.<a name="line.242"></a>
<span class="sourceLineNo">243</span>     *<a name="line.243"></a>
<span class="sourceLineNo">244</span>     * @param name Name of the attribute to return<a name="line.244"></a>
<span class="sourceLineNo">245</span>     */<a name="line.245"></a>
<span class="sourceLineNo">246</span>    public Object getAttribute(String name) {<a name="line.246"></a>
<span class="sourceLineNo">247</span>        return attributes.get(name);<a name="line.247"></a>
<span class="sourceLineNo">248</span>    }<a name="line.248"></a>
<span class="sourceLineNo">249</span><a name="line.249"></a>
<span class="sourceLineNo">250</span>    /**<a name="line.250"></a>
<span class="sourceLineNo">251</span>     * Return an array containing the names of all currently defined<a name="line.251"></a>
<span class="sourceLineNo">252</span>     * configuration attributes.  If there are no such attributes, a zero<a name="line.252"></a>
<span class="sourceLineNo">253</span>     * length array is returned.<a name="line.253"></a>
<span class="sourceLineNo">254</span>     */<a name="line.254"></a>
<span class="sourceLineNo">255</span>    public String[] getAttributeNames() {<a name="line.255"></a>
<span class="sourceLineNo">256</span>        return (String[]) attributes.keySet().toArray(new String[attributes.size()]);<a name="line.256"></a>
<span class="sourceLineNo">257</span>    }<a name="line.257"></a>
<span class="sourceLineNo">258</span><a name="line.258"></a>
<span class="sourceLineNo">259</span>    /**<a name="line.259"></a>
<span class="sourceLineNo">260</span>     * Convenience method to derive a name from the specified class and<a name="line.260"></a>
<span class="sourceLineNo">261</span>     * call &lt;code&gt;getInstance(String)&lt;/code&gt; with it.<a name="line.261"></a>
<span class="sourceLineNo">262</span>     *<a name="line.262"></a>
<span class="sourceLineNo">263</span>     * @param clazz Class for which a suitable Log name will be derived<a name="line.263"></a>
<span class="sourceLineNo">264</span>     *<a name="line.264"></a>
<span class="sourceLineNo">265</span>     * @exception LogConfigurationException if a suitable &lt;code&gt;Log&lt;/code&gt;<a name="line.265"></a>
<span class="sourceLineNo">266</span>     *  instance cannot be returned<a name="line.266"></a>
<span class="sourceLineNo">267</span>     */<a name="line.267"></a>
<span class="sourceLineNo">268</span>    public Log getInstance(Class clazz) throws LogConfigurationException {<a name="line.268"></a>
<span class="sourceLineNo">269</span>        return getInstance(clazz.getName());<a name="line.269"></a>
<span class="sourceLineNo">270</span>    }<a name="line.270"></a>
<span class="sourceLineNo">271</span><a name="line.271"></a>
<span class="sourceLineNo">272</span>    /**<a name="line.272"></a>
<span class="sourceLineNo">273</span>     * &lt;p&gt;Construct (if necessary) and return a &lt;code&gt;Log&lt;/code&gt; instance,<a name="line.273"></a>
<span class="sourceLineNo">274</span>     * using the factory's current set of configuration attributes.&lt;/p&gt;<a name="line.274"></a>
<span class="sourceLineNo">275</span>     *<a name="line.275"></a>
<span class="sourceLineNo">276</span>     * &lt;p&gt;&lt;strong&gt;NOTE&lt;/strong&gt; - Depending upon the implementation of<a name="line.276"></a>
<span class="sourceLineNo">277</span>     * the &lt;code&gt;LogFactory&lt;/code&gt; you are using, the &lt;code&gt;Log&lt;/code&gt;<a name="line.277"></a>
<span class="sourceLineNo">278</span>     * instance you are returned may or may not be local to the current<a name="line.278"></a>
<span class="sourceLineNo">279</span>     * application, and may or may not be returned again on a subsequent<a name="line.279"></a>
<span class="sourceLineNo">280</span>     * call with the same name argument.&lt;/p&gt;<a name="line.280"></a>
<span class="sourceLineNo">281</span>     *<a name="line.281"></a>
<span class="sourceLineNo">282</span>     * @param name Logical name of the &lt;code&gt;Log&lt;/code&gt; instance to be<a name="line.282"></a>
<span class="sourceLineNo">283</span>     *  returned (the meaning of this name is only known to the underlying<a name="line.283"></a>
<span class="sourceLineNo">284</span>     *  logging implementation that is being wrapped)<a name="line.284"></a>
<span class="sourceLineNo">285</span>     *<a name="line.285"></a>
<span class="sourceLineNo">286</span>     * @exception LogConfigurationException if a suitable &lt;code&gt;Log&lt;/code&gt;<a name="line.286"></a>
<span class="sourceLineNo">287</span>     *  instance cannot be returned<a name="line.287"></a>
<span class="sourceLineNo">288</span>     */<a name="line.288"></a>
<span class="sourceLineNo">289</span>    public Log getInstance(String name) throws LogConfigurationException {<a name="line.289"></a>
<span class="sourceLineNo">290</span>        Log instance = (Log) instances.get(name);<a name="line.290"></a>
<span class="sourceLineNo">291</span>        if (instance == null) {<a name="line.291"></a>
<span class="sourceLineNo">292</span>            instance = newInstance(name);<a name="line.292"></a>
<span class="sourceLineNo">293</span>            instances.put(name, instance);<a name="line.293"></a>
<span class="sourceLineNo">294</span>        }<a name="line.294"></a>
<span class="sourceLineNo">295</span>        return instance;<a name="line.295"></a>
<span class="sourceLineNo">296</span>    }<a name="line.296"></a>
<span class="sourceLineNo">297</span><a name="line.297"></a>
<span class="sourceLineNo">298</span>    /**<a name="line.298"></a>
<span class="sourceLineNo">299</span>     * Release any internal references to previously created<a name="line.299"></a>
<span class="sourceLineNo">300</span>     * {@link org.apache.commons.logging.Log}<a name="line.300"></a>
<span class="sourceLineNo">301</span>     * instances returned by this factory.  This is useful in environments<a name="line.301"></a>
<span class="sourceLineNo">302</span>     * like servlet containers, which implement application reloading by<a name="line.302"></a>
<span class="sourceLineNo">303</span>     * throwing away a ClassLoader.  Dangling references to objects in that<a name="line.303"></a>
<span class="sourceLineNo">304</span>     * class loader would prevent garbage collection.<a name="line.304"></a>
<span class="sourceLineNo">305</span>     */<a name="line.305"></a>
<span class="sourceLineNo">306</span>    public void release() {<a name="line.306"></a>
<span class="sourceLineNo">307</span><a name="line.307"></a>
<span class="sourceLineNo">308</span>        logDiagnostic("Releasing all known loggers");<a name="line.308"></a>
<span class="sourceLineNo">309</span>        instances.clear();<a name="line.309"></a>
<span class="sourceLineNo">310</span>    }<a name="line.310"></a>
<span class="sourceLineNo">311</span><a name="line.311"></a>
<span class="sourceLineNo">312</span>    /**<a name="line.312"></a>
<span class="sourceLineNo">313</span>     * Remove any configuration attribute associated with the specified name.<a name="line.313"></a>
<span class="sourceLineNo">314</span>     * If there is no such attribute, no action is taken.<a name="line.314"></a>
<span class="sourceLineNo">315</span>     *<a name="line.315"></a>
<span class="sourceLineNo">316</span>     * @param name Name of the attribute to remove<a name="line.316"></a>
<span class="sourceLineNo">317</span>     */<a name="line.317"></a>
<span class="sourceLineNo">318</span>    public void removeAttribute(String name) {<a name="line.318"></a>
<span class="sourceLineNo">319</span>        attributes.remove(name);<a name="line.319"></a>
<span class="sourceLineNo">320</span>    }<a name="line.320"></a>
<span class="sourceLineNo">321</span><a name="line.321"></a>
<span class="sourceLineNo">322</span>    /**<a name="line.322"></a>
<span class="sourceLineNo">323</span>     * Set the configuration attribute with the specified name.  Calling<a name="line.323"></a>
<span class="sourceLineNo">324</span>     * this with a &lt;code&gt;null&lt;/code&gt; value is equivalent to calling<a name="line.324"></a>
<span class="sourceLineNo">325</span>     * &lt;code&gt;removeAttribute(name)&lt;/code&gt;.<a name="line.325"></a>
<span class="sourceLineNo">326</span>     * &lt;p&gt;<a name="line.326"></a>
<span class="sourceLineNo">327</span>     * This method can be used to set logging configuration programmatically<a name="line.327"></a>
<span class="sourceLineNo">328</span>     * rather than via system properties. It can also be used in code running<a name="line.328"></a>
<span class="sourceLineNo">329</span>     * within a container (such as a webapp) to configure behaviour on a<a name="line.329"></a>
<span class="sourceLineNo">330</span>     * per-component level instead of globally as system properties would do.<a name="line.330"></a>
<span class="sourceLineNo">331</span>     * To use this method instead of a system property, call<a name="line.331"></a>
<span class="sourceLineNo">332</span>     * &lt;pre&gt;<a name="line.332"></a>
<span class="sourceLineNo">333</span>     * LogFactory.getFactory().setAttribute(...)<a name="line.333"></a>
<span class="sourceLineNo">334</span>     * &lt;/pre&gt;<a name="line.334"></a>
<span class="sourceLineNo">335</span>     * This must be done before the first Log object is created; configuration<a name="line.335"></a>
<span class="sourceLineNo">336</span>     * changes after that point will be ignored.<a name="line.336"></a>
<span class="sourceLineNo">337</span>     * &lt;p&gt;<a name="line.337"></a>
<span class="sourceLineNo">338</span>     * This method is also called automatically if LogFactory detects a<a name="line.338"></a>
<span class="sourceLineNo">339</span>     * commons-logging.properties file; every entry in that file is set<a name="line.339"></a>
<span class="sourceLineNo">340</span>     * automatically as an attribute here.<a name="line.340"></a>
<span class="sourceLineNo">341</span>     *<a name="line.341"></a>
<span class="sourceLineNo">342</span>     * @param name Name of the attribute to set<a name="line.342"></a>
<span class="sourceLineNo">343</span>     * @param value Value of the attribute to set, or &lt;code&gt;null&lt;/code&gt;<a name="line.343"></a>
<span class="sourceLineNo">344</span>     *  to remove any setting for this attribute<a name="line.344"></a>
<span class="sourceLineNo">345</span>     */<a name="line.345"></a>
<span class="sourceLineNo">346</span>    public void setAttribute(String name, Object value) {<a name="line.346"></a>
<span class="sourceLineNo">347</span>        if (logConstructor != null) {<a name="line.347"></a>
<span class="sourceLineNo">348</span>            logDiagnostic("setAttribute: call too late; configuration already performed.");<a name="line.348"></a>
<span class="sourceLineNo">349</span>        }<a name="line.349"></a>
<span class="sourceLineNo">350</span><a name="line.350"></a>
<span class="sourceLineNo">351</span>        if (value == null) {<a name="line.351"></a>
<span class="sourceLineNo">352</span>            attributes.remove(name);<a name="line.352"></a>
<span class="sourceLineNo">353</span>        } else {<a name="line.353"></a>
<span class="sourceLineNo">354</span>            attributes.put(name, value);<a name="line.354"></a>
<span class="sourceLineNo">355</span>        }<a name="line.355"></a>
<span class="sourceLineNo">356</span><a name="line.356"></a>
<span class="sourceLineNo">357</span>        if (name.equals(TCCL_KEY)) {<a name="line.357"></a>
<span class="sourceLineNo">358</span>            useTCCL = value != null &amp;&amp; Boolean.valueOf(value.toString()).booleanValue();<a name="line.358"></a>
<span class="sourceLineNo">359</span>        }<a name="line.359"></a>
<span class="sourceLineNo">360</span>    }<a name="line.360"></a>
<span class="sourceLineNo">361</span><a name="line.361"></a>
<span class="sourceLineNo">362</span>    // ------------------------------------------------------<a name="line.362"></a>
<span class="sourceLineNo">363</span>    // Static Methods<a name="line.363"></a>
<span class="sourceLineNo">364</span>    //<a name="line.364"></a>
<span class="sourceLineNo">365</span>    // These methods only defined as workarounds for a java 1.2 bug;<a name="line.365"></a>
<span class="sourceLineNo">366</span>    // theoretically none of these are needed.<a name="line.366"></a>
<span class="sourceLineNo">367</span>    // ------------------------------------------------------<a name="line.367"></a>
<span class="sourceLineNo">368</span><a name="line.368"></a>
<span class="sourceLineNo">369</span>    /**<a name="line.369"></a>
<span class="sourceLineNo">370</span>     * Gets the context classloader.<a name="line.370"></a>
<span class="sourceLineNo">371</span>     * This method is a workaround for a java 1.2 compiler bug.<a name="line.371"></a>
<span class="sourceLineNo">372</span>     * @since 1.1<a name="line.372"></a>
<span class="sourceLineNo">373</span>     */<a name="line.373"></a>
<span class="sourceLineNo">374</span>    protected static ClassLoader getContextClassLoader() throws LogConfigurationException {<a name="line.374"></a>
<span class="sourceLineNo">375</span>        return LogFactory.getContextClassLoader();<a name="line.375"></a>
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<span class="sourceLineNo">377</span><a name="line.377"></a>
<span class="sourceLineNo">378</span>    /**<a name="line.378"></a>
<span class="sourceLineNo">379</span>     * Workaround for bug in Java1.2; in theory this method is not needed.<a name="line.379"></a>
<span class="sourceLineNo">380</span>     * See LogFactory.isDiagnosticsEnabled.<a name="line.380"></a>
<span class="sourceLineNo">381</span>     */<a name="line.381"></a>
<span class="sourceLineNo">382</span>    protected static boolean isDiagnosticsEnabled() {<a name="line.382"></a>
<span class="sourceLineNo">383</span>        return LogFactory.isDiagnosticsEnabled();<a name="line.383"></a>
<span class="sourceLineNo">384</span>    }<a name="line.384"></a>
<span class="sourceLineNo">385</span><a name="line.385"></a>
<span class="sourceLineNo">386</span>    /**<a name="line.386"></a>
<span class="sourceLineNo">387</span>     * Workaround for bug in Java1.2; in theory this method is not needed.<a name="line.387"></a>
<span class="sourceLineNo">388</span>     * See LogFactory.getClassLoader.<a name="line.388"></a>
<span class="sourceLineNo">389</span>     * @since 1.1<a name="line.389"></a>
<span class="sourceLineNo">390</span>     */<a name="line.390"></a>
<span class="sourceLineNo">391</span>    protected static ClassLoader getClassLoader(Class clazz) {<a name="line.391"></a>
<span class="sourceLineNo">392</span>        return LogFactory.getClassLoader(clazz);<a name="line.392"></a>
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<span class="sourceLineNo">394</span><a name="line.394"></a>
<span class="sourceLineNo">395</span>    // ------------------------------------------------------ Protected Methods<a name="line.395"></a>
<span class="sourceLineNo">396</span><a name="line.396"></a>
<span class="sourceLineNo">397</span>    /**<a name="line.397"></a>
<span class="sourceLineNo">398</span>     * Calculate and cache a string that uniquely identifies this instance,<a name="line.398"></a>
<span class="sourceLineNo">399</span>     * including which classloader the object was loaded from.<a name="line.399"></a>
<span class="sourceLineNo">400</span>     * &lt;p&gt;<a name="line.400"></a>
<span class="sourceLineNo">401</span>     * This string will later be prefixed to each "internal logging" message<a name="line.401"></a>
<span class="sourceLineNo">402</span>     * emitted, so that users can clearly see any unexpected behaviour.<a name="line.402"></a>
<span class="sourceLineNo">403</span>     * &lt;p&gt;<a name="line.403"></a>
<span class="sourceLineNo">404</span>     * Note that this method does not detect whether internal logging is<a name="line.404"></a>
<span class="sourceLineNo">405</span>     * enabled or not, nor where to output stuff if it is; that is all<a name="line.405"></a>
<span class="sourceLineNo">406</span>     * handled by the parent LogFactory class. This method just computes<a name="line.406"></a>
<span class="sourceLineNo">407</span>     * its own unique prefix for log messages.<a name="line.407"></a>
<span class="sourceLineNo">408</span>     */<a name="line.408"></a>
<span class="sourceLineNo">409</span>    private void initDiagnostics() {<a name="line.409"></a>
<span class="sourceLineNo">410</span>        // It would be nice to include an identifier of the context classloader<a name="line.410"></a>
<span class="sourceLineNo">411</span>        // that this LogFactoryImpl object is responsible for. However that<a name="line.411"></a>
<span class="sourceLineNo">412</span>        // isn't possible as that information isn't available. It is possible<a name="line.412"></a>
<span class="sourceLineNo">413</span>        // to figure this out by looking at the logging from LogFactory to<a name="line.413"></a>
<span class="sourceLineNo">414</span>        // see the context &amp; impl ids from when this object was instantiated,<a name="line.414"></a>
<span class="sourceLineNo">415</span>        // in order to link the impl id output as this object's prefix back to<a name="line.415"></a>
<span class="sourceLineNo">416</span>        // the context it is intended to manage.<a name="line.416"></a>
<span class="sourceLineNo">417</span>        // Note that this prefix should be kept consistent with that<a name="line.417"></a>
<span class="sourceLineNo">418</span>        // in LogFactory.<a name="line.418"></a>
<span class="sourceLineNo">419</span>        Class clazz = this.getClass();<a name="line.419"></a>
<span class="sourceLineNo">420</span>        ClassLoader classLoader = getClassLoader(clazz);<a name="line.420"></a>
<span class="sourceLineNo">421</span>        String classLoaderName;<a name="line.421"></a>
<span class="sourceLineNo">422</span>        try {<a name="line.422"></a>
<span class="sourceLineNo">423</span>            if (classLoader == null) {<a name="line.423"></a>
<span class="sourceLineNo">424</span>                classLoaderName = "BOOTLOADER";<a name="line.424"></a>
<span class="sourceLineNo">425</span>            } else {<a name="line.425"></a>
<span class="sourceLineNo">426</span>                classLoaderName = objectId(classLoader);<a name="line.426"></a>
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<span class="sourceLineNo">428</span>        } catch (SecurityException e) {<a name="line.428"></a>
<span class="sourceLineNo">429</span>            classLoaderName = "UNKNOWN";<a name="line.429"></a>
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<span class="sourceLineNo">431</span>        diagnosticPrefix = "[LogFactoryImpl@" + System.identityHashCode(this) + " from " + classLoaderName + "] ";<a name="line.431"></a>
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<span class="sourceLineNo">433</span><a name="line.433"></a>
<span class="sourceLineNo">434</span>    /**<a name="line.434"></a>
<span class="sourceLineNo">435</span>     * Output a diagnostic message to a user-specified destination (if the<a name="line.435"></a>
<span class="sourceLineNo">436</span>     * user has enabled diagnostic logging).<a name="line.436"></a>
<span class="sourceLineNo">437</span>     *<a name="line.437"></a>
<span class="sourceLineNo">438</span>     * @param msg diagnostic message<a name="line.438"></a>
<span class="sourceLineNo">439</span>     * @since 1.1<a name="line.439"></a>
<span class="sourceLineNo">440</span>     */<a name="line.440"></a>
<span class="sourceLineNo">441</span>    protected void logDiagnostic(String msg) {<a name="line.441"></a>
<span class="sourceLineNo">442</span>        if (isDiagnosticsEnabled()) {<a name="line.442"></a>
<span class="sourceLineNo">443</span>            logRawDiagnostic(diagnosticPrefix + msg);<a name="line.443"></a>
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<span class="sourceLineNo">445</span>    }<a name="line.445"></a>
<span class="sourceLineNo">446</span><a name="line.446"></a>
<span class="sourceLineNo">447</span>    /**<a name="line.447"></a>
<span class="sourceLineNo">448</span>     * Return the fully qualified Java classname of the {@link Log}<a name="line.448"></a>
<span class="sourceLineNo">449</span>     * implementation we will be using.<a name="line.449"></a>
<span class="sourceLineNo">450</span>     *<a name="line.450"></a>
<span class="sourceLineNo">451</span>     * @deprecated  Never invoked by this class; subclasses should not assume<a name="line.451"></a>
<span class="sourceLineNo">452</span>     *              it will be.<a name="line.452"></a>
<span class="sourceLineNo">453</span>     */<a name="line.453"></a>
<span class="sourceLineNo">454</span>    protected String getLogClassName() {<a name="line.454"></a>
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<span class="sourceLineNo">456</span>            discoverLogImplementation(getClass().getName());<a name="line.456"></a>
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<span class="sourceLineNo">458</span><a name="line.458"></a>
<span class="sourceLineNo">459</span>        return logClassName;<a name="line.459"></a>
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<span class="sourceLineNo">461</span><a name="line.461"></a>
<span class="sourceLineNo">462</span><a name="line.462"></a>
<span class="sourceLineNo">463</span>    /**<a name="line.463"></a>
<span class="sourceLineNo">464</span>     * &lt;p&gt;Return the &lt;code&gt;Constructor&lt;/code&gt; that can be called to instantiate<a name="line.464"></a>
<span class="sourceLineNo">465</span>     * new {@link org.apache.commons.logging.Log} instances.&lt;/p&gt;<a name="line.465"></a>
<span class="sourceLineNo">466</span>     *<a name="line.466"></a>
<span class="sourceLineNo">467</span>     * &lt;p&gt;&lt;strong&gt;IMPLEMENTATION NOTE&lt;/strong&gt; - Race conditions caused by<a name="line.467"></a>
<span class="sourceLineNo">468</span>     * calling this method from more than one thread are ignored, because<a name="line.468"></a>
<span class="sourceLineNo">469</span>     * the same &lt;code&gt;Constructor&lt;/code&gt; instance will ultimately be derived<a name="line.469"></a>
<span class="sourceLineNo">470</span>     * in all circumstances.&lt;/p&gt;<a name="line.470"></a>
<span class="sourceLineNo">471</span>     *<a name="line.471"></a>
<span class="sourceLineNo">472</span>     * @exception LogConfigurationException if a suitable constructor<a name="line.472"></a>
<span class="sourceLineNo">473</span>     *  cannot be returned<a name="line.473"></a>
<span class="sourceLineNo">474</span>     *<a name="line.474"></a>
<span class="sourceLineNo">475</span>     * @deprecated  Never invoked by this class; subclasses should not assume<a name="line.475"></a>
<span class="sourceLineNo">476</span>     *              it will be.<a name="line.476"></a>
<span class="sourceLineNo">477</span>     */<a name="line.477"></a>
<span class="sourceLineNo">478</span>    protected Constructor getLogConstructor()<a name="line.478"></a>
<span class="sourceLineNo">479</span>        throws LogConfigurationException {<a name="line.479"></a>
<span class="sourceLineNo">480</span><a name="line.480"></a>
<span class="sourceLineNo">481</span>        // Return the previously identified Constructor (if any)<a name="line.481"></a>
<span class="sourceLineNo">482</span>        if (logConstructor == null) {<a name="line.482"></a>
<span class="sourceLineNo">483</span>            discoverLogImplementation(getClass().getName());<a name="line.483"></a>
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<span class="sourceLineNo">485</span><a name="line.485"></a>
<span class="sourceLineNo">486</span>        return logConstructor;<a name="line.486"></a>
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<span class="sourceLineNo">798</span>                // Mistyping or misspelling names is a common fault.<a name="line.798"></a>
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<span class="sourceLineNo">810</span>        // No user specified log; try to discover what's on the classpath<a name="line.810"></a>
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<span class="sourceLineNo">813</span>        // expect method createLogFromClass to loop over the possible source<a name="line.813"></a>
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<span class="sourceLineNo">882</span>     * a Log implementation specified by the user under the<a name="line.882"></a>
<span class="sourceLineNo">883</span>     * property names {@link #LOG_PROPERTY} or {@link #LOG_PROPERTY_OLD}.<a name="line.883"></a>
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<span class="sourceLineNo">904</span>                          LOG_PROPERTY + "'");<a name="line.904"></a>
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<span class="sourceLineNo">911</span>                        LOG_PROPERTY + "' - " + e.getMessage());<a name="line.911"></a>
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<span class="sourceLineNo">973</span>            // a viable classloader.<a name="line.973"></a>
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<span class="sourceLineNo">984</span>                        url = currentCL.getResource(resourceName );<a name="line.984"></a>
<span class="sourceLineNo">985</span>                    } else {<a name="line.985"></a>
<span class="sourceLineNo">986</span>                        url = ClassLoader.getSystemResource(resourceName + ".class");<a name="line.986"></a>
<span class="sourceLineNo">987</span>                    }<a name="line.987"></a>
<span class="sourceLineNo">988</span><a name="line.988"></a>
<span class="sourceLineNo">989</span>                    if (url == null) {<a name="line.989"></a>
<span class="sourceLineNo">990</span>                        logDiagnostic("Class '" + logAdapterClassName + "' [" + resourceName + "] cannot be found.");<a name="line.990"></a>
<span class="sourceLineNo">991</span>                    } else {<a name="line.991"></a>
<span class="sourceLineNo">992</span>                        logDiagnostic("Class '" + logAdapterClassName + "' was found at '" + url + "'");<a name="line.992"></a>
<span class="sourceLineNo">993</span>                    }<a name="line.993"></a>
<span class="sourceLineNo">994</span>                }<a name="line.994"></a>
<span class="sourceLineNo">995</span><a name="line.995"></a>
<span class="sourceLineNo">996</span>                Class c;<a name="line.996"></a>
<span class="sourceLineNo">997</span>                try {<a name="line.997"></a>
<span class="sourceLineNo">998</span>                    c = Class.forName(logAdapterClassName, true, currentCL);<a name="line.998"></a>
<span class="sourceLineNo">999</span>                } catch (ClassNotFoundException originalClassNotFoundException) {<a name="line.999"></a>
<span class="sourceLineNo">1000</span>                    // The current classloader was unable to find the log adapter<a name="line.1000"></a>
<span class="sourceLineNo">1001</span>                    // in this or any ancestor classloader. There's no point in<a name="line.1001"></a>
<span class="sourceLineNo">1002</span>                    // trying higher up in the hierarchy in this case..<a name="line.1002"></a>
<span class="sourceLineNo">1003</span>                    String msg = originalClassNotFoundException.getMessage();<a name="line.1003"></a>
<span class="sourceLineNo">1004</span>                    logDiagnostic("The log adapter '" + logAdapterClassName + "' is not available via classloader " +<a name="line.1004"></a>
<span class="sourceLineNo">1005</span>                                  objectId(currentCL) + ": " + msg.trim());<a name="line.1005"></a>
<span class="sourceLineNo">1006</span>                    try {<a name="line.1006"></a>
<span class="sourceLineNo">1007</span>                        // Try the class classloader.<a name="line.1007"></a>
<span class="sourceLineNo">1008</span>                        // This may work in cases where the TCCL<a name="line.1008"></a>
<span class="sourceLineNo">1009</span>                        // does not contain the code executed or JCL.<a name="line.1009"></a>
<span class="sourceLineNo">1010</span>                        // This behaviour indicates that the application<a name="line.1010"></a>
<span class="sourceLineNo">1011</span>                        // classloading strategy is not consistent with the<a name="line.1011"></a>
<span class="sourceLineNo">1012</span>                        // Java 1.2 classloading guidelines but JCL can<a name="line.1012"></a>
<span class="sourceLineNo">1013</span>                        // and so should handle this case.<a name="line.1013"></a>
<span class="sourceLineNo">1014</span>                        c = Class.forName(logAdapterClassName);<a name="line.1014"></a>
<span class="sourceLineNo">1015</span>                    } catch (ClassNotFoundException secondaryClassNotFoundException) {<a name="line.1015"></a>
<span class="sourceLineNo">1016</span>                        // no point continuing: this adapter isn't available<a name="line.1016"></a>
<span class="sourceLineNo">1017</span>                        msg = secondaryClassNotFoundException.getMessage();<a name="line.1017"></a>
<span class="sourceLineNo">1018</span>                        logDiagnostic("The log adapter '" + logAdapterClassName +<a name="line.1018"></a>
<span class="sourceLineNo">1019</span>                                      "' is not available via the LogFactoryImpl class classloader: " + msg.trim());<a name="line.1019"></a>
<span class="sourceLineNo">1020</span>                        break;<a name="line.1020"></a>
<span class="sourceLineNo">1021</span>                    }<a name="line.1021"></a>
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<span class="sourceLineNo">1024</span>                constructor = c.getConstructor(logConstructorSignature);<a name="line.1024"></a>
<span class="sourceLineNo">1025</span>                Object o = constructor.newInstance(params);<a name="line.1025"></a>
<span class="sourceLineNo">1026</span><a name="line.1026"></a>
<span class="sourceLineNo">1027</span>                // Note that we do this test after trying to create an instance<a name="line.1027"></a>
<span class="sourceLineNo">1028</span>                // [rather than testing Log.class.isAssignableFrom(c)] so that<a name="line.1028"></a>
<span class="sourceLineNo">1029</span>                // we don't complain about Log hierarchy problems when the<a name="line.1029"></a>
<span class="sourceLineNo">1030</span>                // adapter couldn't be instantiated anyway.<a name="line.1030"></a>
<span class="sourceLineNo">1031</span>                if (o instanceof Log) {<a name="line.1031"></a>
<span class="sourceLineNo">1032</span>                    logAdapterClass = c;<a name="line.1032"></a>
<span class="sourceLineNo">1033</span>                    logAdapter = (Log) o;<a name="line.1033"></a>
<span class="sourceLineNo">1034</span>                    break;<a name="line.1034"></a>
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<span class="sourceLineNo">1036</span><a name="line.1036"></a>
<span class="sourceLineNo">1037</span>                // Oops, we have a potential problem here. An adapter class<a name="line.1037"></a>
<span class="sourceLineNo">1038</span>                // has been found and its underlying lib is present too, but<a name="line.1038"></a>
<span class="sourceLineNo">1039</span>                // there are multiple Log interface classes available making it<a name="line.1039"></a>
<span class="sourceLineNo">1040</span>                // impossible to cast to the type the caller wanted. We<a name="line.1040"></a>
<span class="sourceLineNo">1041</span>                // certainly can't use this logger, but we need to know whether<a name="line.1041"></a>
<span class="sourceLineNo">1042</span>                // to keep on discovering or terminate now.<a name="line.1042"></a>
<span class="sourceLineNo">1043</span>                //<a name="line.1043"></a>
<span class="sourceLineNo">1044</span>                // The handleFlawedHierarchy method will throw<a name="line.1044"></a>
<span class="sourceLineNo">1045</span>                // LogConfigurationException if it regards this problem as<a name="line.1045"></a>
<span class="sourceLineNo">1046</span>                // fatal, and just return if not.<a name="line.1046"></a>
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<span class="sourceLineNo">1049</span>                // We were able to load the adapter but it had references to<a name="line.1049"></a>
<span class="sourceLineNo">1050</span>                // other classes that could not be found. This simply means that<a name="line.1050"></a>
<span class="sourceLineNo">1051</span>                // the underlying logger library is not present in this or any<a name="line.1051"></a>
<span class="sourceLineNo">1052</span>                // ancestor classloader. There's no point in trying higher up<a name="line.1052"></a>
<span class="sourceLineNo">1053</span>                // in the hierarchy in this case..<a name="line.1053"></a>
<span class="sourceLineNo">1054</span>                String msg = e.getMessage();<a name="line.1054"></a>
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<span class="sourceLineNo">1056</span>                              "' is missing dependencies when loaded via classloader " + objectId(currentCL) +<a name="line.1056"></a>
<span class="sourceLineNo">1057</span>                              ": " + msg.trim());<a name="line.1057"></a>
<span class="sourceLineNo">1058</span>                break;<a name="line.1058"></a>
<span class="sourceLineNo">1059</span>            } catch (ExceptionInInitializerError e) {<a name="line.1059"></a>
<span class="sourceLineNo">1060</span>                // A static initializer block or the initializer code associated<a name="line.1060"></a>
<span class="sourceLineNo">1061</span>                // with a static variable on the log adapter class has thrown<a name="line.1061"></a>
<span class="sourceLineNo">1062</span>                // an exception.<a name="line.1062"></a>
<span class="sourceLineNo">1063</span>                //<a name="line.1063"></a>
<span class="sourceLineNo">1064</span>                // We treat this as meaning the adapter's underlying logging<a name="line.1064"></a>
<span class="sourceLineNo">1065</span>                // library could not be found.<a name="line.1065"></a>
<span class="sourceLineNo">1066</span>                String msg = e.getMessage();<a name="line.1066"></a>
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<span class="sourceLineNo">1068</span>                              "' is unable to initialize itself when loaded via classloader " + objectId(currentCL) +<a name="line.1068"></a>
<span class="sourceLineNo">1069</span>                              ": " + msg.trim());<a name="line.1069"></a>
<span class="sourceLineNo">1070</span>                break;<a name="line.1070"></a>
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<span class="sourceLineNo">1072</span>                // call to handleFlawedHierarchy above must have thrown<a name="line.1072"></a>
<span class="sourceLineNo">1073</span>                // a LogConfigurationException, so just throw it on<a name="line.1073"></a>
<span class="sourceLineNo">1074</span>                throw e;<a name="line.1074"></a>
<span class="sourceLineNo">1075</span>            } catch (Throwable t) {<a name="line.1075"></a>
<span class="sourceLineNo">1076</span>                handleThrowable(t); // may re-throw t<a name="line.1076"></a>
<span class="sourceLineNo">1077</span>                // handleFlawedDiscovery will determine whether this is a fatal<a name="line.1077"></a>
<span class="sourceLineNo">1078</span>                // problem or not. If it is fatal, then a LogConfigurationException<a name="line.1078"></a>
<span class="sourceLineNo">1079</span>                // will be thrown.<a name="line.1079"></a>
<span class="sourceLineNo">1080</span>                handleFlawedDiscovery(logAdapterClassName, currentCL, t);<a name="line.1080"></a>
<span class="sourceLineNo">1081</span>            }<a name="line.1081"></a>
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<span class="sourceLineNo">1083</span>            if (currentCL == null) {<a name="line.1083"></a>
<span class="sourceLineNo">1084</span>                break;<a name="line.1084"></a>
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<span class="sourceLineNo">1087</span>            // try the parent classloader<a name="line.1087"></a>
<span class="sourceLineNo">1088</span>            // currentCL = currentCL.getParent();<a name="line.1088"></a>
<span class="sourceLineNo">1089</span>            currentCL = getParentClassLoader(currentCL);<a name="line.1089"></a>
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<span class="sourceLineNo">1091</span><a name="line.1091"></a>
<span class="sourceLineNo">1092</span>        if (logAdapterClass != null &amp;&amp; affectState) {<a name="line.1092"></a>
<span class="sourceLineNo">1093</span>            // We've succeeded, so set instance fields<a name="line.1093"></a>
<span class="sourceLineNo">1094</span>            this.logClassName   = logAdapterClassName;<a name="line.1094"></a>
<span class="sourceLineNo">1095</span>            this.logConstructor = constructor;<a name="line.1095"></a>
<span class="sourceLineNo">1096</span><a name="line.1096"></a>
<span class="sourceLineNo">1097</span>            // Identify the &lt;code&gt;setLogFactory&lt;/code&gt; method (if there is one)<a name="line.1097"></a>
<span class="sourceLineNo">1098</span>            try {<a name="line.1098"></a>
<span class="sourceLineNo">1099</span>                this.logMethod = logAdapterClass.getMethod("setLogFactory", logMethodSignature);<a name="line.1099"></a>
<span class="sourceLineNo">1100</span>                logDiagnostic("Found method setLogFactory(LogFactory) in '" + logAdapterClassName + "'");<a name="line.1100"></a>
<span class="sourceLineNo">1101</span>            } catch (Throwable t) {<a name="line.1101"></a>
<span class="sourceLineNo">1102</span>                handleThrowable(t); // may re-throw t<a name="line.1102"></a>
<span class="sourceLineNo">1103</span>                this.logMethod = null;<a name="line.1103"></a>
<span class="sourceLineNo">1104</span>                logDiagnostic("[INFO] '" + logAdapterClassName + "' from classloader " + objectId(currentCL) +<a name="line.1104"></a>
<span class="sourceLineNo">1105</span>                              " does not declare optional method " + "setLogFactory(LogFactory)");<a name="line.1105"></a>
<span class="sourceLineNo">1106</span>            }<a name="line.1106"></a>
<span class="sourceLineNo">1107</span><a name="line.1107"></a>
<span class="sourceLineNo">1108</span>            logDiagnostic("Log adapter '" + logAdapterClassName + "' from classloader " +<a name="line.1108"></a>
<span class="sourceLineNo">1109</span>                          objectId(logAdapterClass.getClassLoader()) + " has been selected for use.");<a name="line.1109"></a>
<span class="sourceLineNo">1110</span>        }<a name="line.1110"></a>
<span class="sourceLineNo">1111</span><a name="line.1111"></a>
<span class="sourceLineNo">1112</span>        return logAdapter;<a name="line.1112"></a>
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<span class="sourceLineNo">1114</span><a name="line.1114"></a>
<span class="sourceLineNo">1115</span>    /**<a name="line.1115"></a>
<span class="sourceLineNo">1116</span>     * Return the classloader from which we should try to load the logging<a name="line.1116"></a>
<span class="sourceLineNo">1117</span>     * adapter classes.<a name="line.1117"></a>
<span class="sourceLineNo">1118</span>     * &lt;p&gt;<a name="line.1118"></a>
<span class="sourceLineNo">1119</span>     * This method usually returns the context classloader. However if it<a name="line.1119"></a>
<span class="sourceLineNo">1120</span>     * is discovered that the classloader which loaded this class is a child<a name="line.1120"></a>
<span class="sourceLineNo">1121</span>     * of the context classloader &lt;i&gt;and&lt;/i&gt; the allowFlawedContext option<a name="line.1121"></a>
<span class="sourceLineNo">1122</span>     * has been set then the classloader which loaded this class is returned<a name="line.1122"></a>
<span class="sourceLineNo">1123</span>     * instead.<a name="line.1123"></a>
<span class="sourceLineNo">1124</span>     * &lt;p&gt;<a name="line.1124"></a>
<span class="sourceLineNo">1125</span>     * The only time when the classloader which loaded this class is a<a name="line.1125"></a>
<span class="sourceLineNo">1126</span>     * descendant (rather than the same as or an ancestor of the context<a name="line.1126"></a>
<span class="sourceLineNo">1127</span>     * classloader) is when an app has created custom classloaders but<a name="line.1127"></a>
<span class="sourceLineNo">1128</span>     * failed to correctly set the context classloader. This is a bug in<a name="line.1128"></a>
<span class="sourceLineNo">1129</span>     * the calling application; however we provide the option for JCL to<a name="line.1129"></a>
<span class="sourceLineNo">1130</span>     * simply generate a warning rather than fail outright.<a name="line.1130"></a>
<span class="sourceLineNo">1131</span>     *<a name="line.1131"></a>
<span class="sourceLineNo">1132</span>     */<a name="line.1132"></a>
<span class="sourceLineNo">1133</span>    private ClassLoader getBaseClassLoader() throws LogConfigurationException {<a name="line.1133"></a>
<span class="sourceLineNo">1134</span>        ClassLoader thisClassLoader = getClassLoader(LogFactoryImpl.class);<a name="line.1134"></a>
<span class="sourceLineNo">1135</span><a name="line.1135"></a>
<span class="sourceLineNo">1136</span>        if (!useTCCL) {<a name="line.1136"></a>
<span class="sourceLineNo">1137</span>            return thisClassLoader;<a name="line.1137"></a>
<span class="sourceLineNo">1138</span>        }<a name="line.1138"></a>
<span class="sourceLineNo">1139</span><a name="line.1139"></a>
<span class="sourceLineNo">1140</span>        ClassLoader contextClassLoader = getContextClassLoaderInternal();<a name="line.1140"></a>
<span class="sourceLineNo">1141</span><a name="line.1141"></a>
<span class="sourceLineNo">1142</span>        ClassLoader baseClassLoader = getLowestClassLoader(<a name="line.1142"></a>
<span class="sourceLineNo">1143</span>                contextClassLoader, thisClassLoader);<a name="line.1143"></a>
<span class="sourceLineNo">1144</span><a name="line.1144"></a>
<span class="sourceLineNo">1145</span>        if (baseClassLoader == null) {<a name="line.1145"></a>
<span class="sourceLineNo">1146</span>           // The two classloaders are not part of a parent child relationship.<a name="line.1146"></a>
<span class="sourceLineNo">1147</span>           // In some classloading setups (e.g. JBoss with its<a name="line.1147"></a>
<span class="sourceLineNo">1148</span>           // UnifiedLoaderRepository) this can still work, so if user hasn't<a name="line.1148"></a>
<span class="sourceLineNo">1149</span>           // forbidden it, just return the contextClassLoader.<a name="line.1149"></a>
<span class="sourceLineNo">1150</span>           if (allowFlawedContext) {<a name="line.1150"></a>
<span class="sourceLineNo">1151</span>              if (isDiagnosticsEnabled()) {<a name="line.1151"></a>
<span class="sourceLineNo">1152</span>                   logDiagnostic("[WARNING] the context classloader is not part of a" +<a name="line.1152"></a>
<span class="sourceLineNo">1153</span>                                 " parent-child relationship with the classloader that" +<a name="line.1153"></a>
<span class="sourceLineNo">1154</span>                                 " loaded LogFactoryImpl.");<a name="line.1154"></a>
<span class="sourceLineNo">1155</span>              }<a name="line.1155"></a>
<span class="sourceLineNo">1156</span>              // If contextClassLoader were null, getLowestClassLoader() would<a name="line.1156"></a>
<span class="sourceLineNo">1157</span>              // have returned thisClassLoader.  The fact we are here means<a name="line.1157"></a>
<span class="sourceLineNo">1158</span>              // contextClassLoader is not null, so we can just return it.<a name="line.1158"></a>
<span class="sourceLineNo">1159</span>              return contextClassLoader;<a name="line.1159"></a>
<span class="sourceLineNo">1160</span>           }<a name="line.1160"></a>
<span class="sourceLineNo">1161</span>           else {<a name="line.1161"></a>
<span class="sourceLineNo">1162</span>            throw new LogConfigurationException("Bad classloader hierarchy; LogFactoryImpl was loaded via" +<a name="line.1162"></a>
<span class="sourceLineNo">1163</span>                                                " a classloader that is not related to the current context" +<a name="line.1163"></a>
<span class="sourceLineNo">1164</span>                                                " classloader.");<a name="line.1164"></a>
<span class="sourceLineNo">1165</span>           }<a name="line.1165"></a>
<span class="sourceLineNo">1166</span>        }<a name="line.1166"></a>
<span class="sourceLineNo">1167</span><a name="line.1167"></a>
<span class="sourceLineNo">1168</span>        if (baseClassLoader != contextClassLoader) {<a name="line.1168"></a>
<span class="sourceLineNo">1169</span>            // We really should just use the contextClassLoader as the starting<a name="line.1169"></a>
<span class="sourceLineNo">1170</span>            // point for scanning for log adapter classes. However it is expected<a name="line.1170"></a>
<span class="sourceLineNo">1171</span>            // that there are a number of broken systems out there which create<a name="line.1171"></a>
<span class="sourceLineNo">1172</span>            // custom classloaders but fail to set the context classloader so<a name="line.1172"></a>
<span class="sourceLineNo">1173</span>            // we handle those flawed systems anyway.<a name="line.1173"></a>
<span class="sourceLineNo">1174</span>            if (allowFlawedContext) {<a name="line.1174"></a>
<span class="sourceLineNo">1175</span>                if (isDiagnosticsEnabled()) {<a name="line.1175"></a>
<span class="sourceLineNo">1176</span>                    logDiagnostic(<a name="line.1176"></a>
<span class="sourceLineNo">1177</span>                            "Warning: the context classloader is an ancestor of the" +<a name="line.1177"></a>
<span class="sourceLineNo">1178</span>                            " classloader that loaded LogFactoryImpl; it should be" +<a name="line.1178"></a>
<span class="sourceLineNo">1179</span>                            " the same or a descendant. The application using" +<a name="line.1179"></a>
<span class="sourceLineNo">1180</span>                            " commons-logging should ensure the context classloader" +<a name="line.1180"></a>
<span class="sourceLineNo">1181</span>                            " is used correctly.");<a name="line.1181"></a>
<span class="sourceLineNo">1182</span>                }<a name="line.1182"></a>
<span class="sourceLineNo">1183</span>            } else {<a name="line.1183"></a>
<span class="sourceLineNo">1184</span>                throw new LogConfigurationException(<a name="line.1184"></a>
<span class="sourceLineNo">1185</span>                        "Bad classloader hierarchy; LogFactoryImpl was loaded via" +<a name="line.1185"></a>
<span class="sourceLineNo">1186</span>                        " a classloader that is not related to the current context" +<a name="line.1186"></a>
<span class="sourceLineNo">1187</span>                        " classloader.");<a name="line.1187"></a>
<span class="sourceLineNo">1188</span>            }<a name="line.1188"></a>
<span class="sourceLineNo">1189</span>        }<a name="line.1189"></a>
<span class="sourceLineNo">1190</span><a name="line.1190"></a>
<span class="sourceLineNo">1191</span>        return baseClassLoader;<a name="line.1191"></a>
<span class="sourceLineNo">1192</span>    }<a name="line.1192"></a>
<span class="sourceLineNo">1193</span><a name="line.1193"></a>
<span class="sourceLineNo">1194</span>    /**<a name="line.1194"></a>
<span class="sourceLineNo">1195</span>     * Given two related classloaders, return the one which is a child of<a name="line.1195"></a>
<span class="sourceLineNo">1196</span>     * the other.<a name="line.1196"></a>
<span class="sourceLineNo">1197</span>     * &lt;p&gt;<a name="line.1197"></a>
<span class="sourceLineNo">1198</span>     * @param c1 is a classloader (including the null classloader)<a name="line.1198"></a>
<span class="sourceLineNo">1199</span>     * @param c2 is a classloader (including the null classloader)<a name="line.1199"></a>
<span class="sourceLineNo">1200</span>     *<a name="line.1200"></a>
<span class="sourceLineNo">1201</span>     * @return c1 if it has c2 as an ancestor, c2 if it has c1 as an ancestor,<a name="line.1201"></a>
<span class="sourceLineNo">1202</span>     * and null if neither is an ancestor of the other.<a name="line.1202"></a>
<span class="sourceLineNo">1203</span>     */<a name="line.1203"></a>
<span class="sourceLineNo">1204</span>    private ClassLoader getLowestClassLoader(ClassLoader c1, ClassLoader c2) {<a name="line.1204"></a>
<span class="sourceLineNo">1205</span>        // TODO: use AccessController when dealing with classloaders here<a name="line.1205"></a>
<span class="sourceLineNo">1206</span><a name="line.1206"></a>
<span class="sourceLineNo">1207</span>        if (c1 == null) {<a name="line.1207"></a>
<span class="sourceLineNo">1208</span>            return c2;<a name="line.1208"></a>
<span class="sourceLineNo">1209</span>        }<a name="line.1209"></a>
<span class="sourceLineNo">1210</span><a name="line.1210"></a>
<span class="sourceLineNo">1211</span>        if (c2 == null) {<a name="line.1211"></a>
<span class="sourceLineNo">1212</span>            return c1;<a name="line.1212"></a>
<span class="sourceLineNo">1213</span>        }<a name="line.1213"></a>
<span class="sourceLineNo">1214</span><a name="line.1214"></a>
<span class="sourceLineNo">1215</span>        ClassLoader current;<a name="line.1215"></a>
<span class="sourceLineNo">1216</span><a name="line.1216"></a>
<span class="sourceLineNo">1217</span>        // scan c1's ancestors to find c2<a name="line.1217"></a>
<span class="sourceLineNo">1218</span>        current = c1;<a name="line.1218"></a>
<span class="sourceLineNo">1219</span>        while (current != null) {<a name="line.1219"></a>
<span class="sourceLineNo">1220</span>            if (current == c2) {<a name="line.1220"></a>
<span class="sourceLineNo">1221</span>                return c1;<a name="line.1221"></a>
<span class="sourceLineNo">1222</span>            }<a name="line.1222"></a>
<span class="sourceLineNo">1223</span>            // current = current.getParent();<a name="line.1223"></a>
<span class="sourceLineNo">1224</span>            current = getParentClassLoader(current);<a name="line.1224"></a>
<span class="sourceLineNo">1225</span>        }<a name="line.1225"></a>
<span class="sourceLineNo">1226</span><a name="line.1226"></a>
<span class="sourceLineNo">1227</span>        // scan c2's ancestors to find c1<a name="line.1227"></a>
<span class="sourceLineNo">1228</span>        current = c2;<a name="line.1228"></a>
<span class="sourceLineNo">1229</span>        while (current != null) {<a name="line.1229"></a>
<span class="sourceLineNo">1230</span>            if (current == c1) {<a name="line.1230"></a>
<span class="sourceLineNo">1231</span>                return c2;<a name="line.1231"></a>
<span class="sourceLineNo">1232</span>            }<a name="line.1232"></a>
<span class="sourceLineNo">1233</span>            // current = current.getParent();<a name="line.1233"></a>
<span class="sourceLineNo">1234</span>            current = getParentClassLoader(current);<a name="line.1234"></a>
<span class="sourceLineNo">1235</span>        }<a name="line.1235"></a>
<span class="sourceLineNo">1236</span><a name="line.1236"></a>
<span class="sourceLineNo">1237</span>        return null;<a name="line.1237"></a>
<span class="sourceLineNo">1238</span>    }<a name="line.1238"></a>
<span class="sourceLineNo">1239</span><a name="line.1239"></a>
<span class="sourceLineNo">1240</span>    /**<a name="line.1240"></a>
<span class="sourceLineNo">1241</span>     * Generates an internal diagnostic logging of the discovery failure and<a name="line.1241"></a>
<span class="sourceLineNo">1242</span>     * then throws a &lt;code&gt;LogConfigurationException&lt;/code&gt; that wraps<a name="line.1242"></a>
<span class="sourceLineNo">1243</span>     * the passed &lt;code&gt;Throwable&lt;/code&gt;.<a name="line.1243"></a>
<span class="sourceLineNo">1244</span>     *<a name="line.1244"></a>
<span class="sourceLineNo">1245</span>     * @param logAdapterClassName is the class name of the Log implementation<a name="line.1245"></a>
<span class="sourceLineNo">1246</span>     * that could not be instantiated. Cannot be &lt;code&gt;null&lt;/code&gt;.<a name="line.1246"></a>
<span class="sourceLineNo">1247</span>     *<a name="line.1247"></a>
<span class="sourceLineNo">1248</span>     * @param classLoader is the classloader that we were trying to load the<a name="line.1248"></a>
<span class="sourceLineNo">1249</span>     * logAdapterClassName from when the exception occurred.<a name="line.1249"></a>
<span class="sourceLineNo">1250</span>     *<a name="line.1250"></a>
<span class="sourceLineNo">1251</span>     * @param discoveryFlaw is the Throwable created by the classloader<a name="line.1251"></a>
<span class="sourceLineNo">1252</span>     *<a name="line.1252"></a>
<span class="sourceLineNo">1253</span>     * @throws LogConfigurationException    ALWAYS<a name="line.1253"></a>
<span class="sourceLineNo">1254</span>     */<a name="line.1254"></a>
<span class="sourceLineNo">1255</span>    private void handleFlawedDiscovery(String logAdapterClassName,<a name="line.1255"></a>
<span class="sourceLineNo">1256</span>                                       ClassLoader classLoader, // USED?<a name="line.1256"></a>
<span class="sourceLineNo">1257</span>                                       Throwable discoveryFlaw) {<a name="line.1257"></a>
<span class="sourceLineNo">1258</span><a name="line.1258"></a>
<span class="sourceLineNo">1259</span>        if (isDiagnosticsEnabled()) {<a name="line.1259"></a>
<span class="sourceLineNo">1260</span>            logDiagnostic("Could not instantiate Log '" +<a name="line.1260"></a>
<span class="sourceLineNo">1261</span>                      logAdapterClassName + "' -- " +<a name="line.1261"></a>
<span class="sourceLineNo">1262</span>                      discoveryFlaw.getClass().getName() + ": " +<a name="line.1262"></a>
<span class="sourceLineNo">1263</span>                      discoveryFlaw.getLocalizedMessage());<a name="line.1263"></a>
<span class="sourceLineNo">1264</span><a name="line.1264"></a>
<span class="sourceLineNo">1265</span>            if (discoveryFlaw instanceof InvocationTargetException ) {<a name="line.1265"></a>
<span class="sourceLineNo">1266</span>                // Ok, the lib is there but while trying to create a real underlying<a name="line.1266"></a>
<span class="sourceLineNo">1267</span>                // logger something failed in the underlying lib; display info about<a name="line.1267"></a>
<span class="sourceLineNo">1268</span>                // that if possible.<a name="line.1268"></a>
<span class="sourceLineNo">1269</span>                InvocationTargetException ite = (InvocationTargetException)discoveryFlaw;<a name="line.1269"></a>
<span class="sourceLineNo">1270</span>                Throwable cause = ite.getTargetException();<a name="line.1270"></a>
<span class="sourceLineNo">1271</span>                if (cause != null) {<a name="line.1271"></a>
<span class="sourceLineNo">1272</span>                    logDiagnostic("... InvocationTargetException: " +<a name="line.1272"></a>
<span class="sourceLineNo">1273</span>                        cause.getClass().getName() + ": " +<a name="line.1273"></a>
<span class="sourceLineNo">1274</span>                        cause.getLocalizedMessage());<a name="line.1274"></a>
<span class="sourceLineNo">1275</span><a name="line.1275"></a>
<span class="sourceLineNo">1276</span>                    if (cause instanceof ExceptionInInitializerError) {<a name="line.1276"></a>
<span class="sourceLineNo">1277</span>                        ExceptionInInitializerError eiie = (ExceptionInInitializerError)cause;<a name="line.1277"></a>
<span class="sourceLineNo">1278</span>                        Throwable cause2 = eiie.getException();<a name="line.1278"></a>
<span class="sourceLineNo">1279</span>                        if (cause2 != null) {<a name="line.1279"></a>
<span class="sourceLineNo">1280</span>                            final StringWriter sw = new StringWriter();<a name="line.1280"></a>
<span class="sourceLineNo">1281</span>                            cause2.printStackTrace(new PrintWriter(sw, true));<a name="line.1281"></a>
<span class="sourceLineNo">1282</span>                            logDiagnostic("... ExceptionInInitializerError: " + sw.toString());<a name="line.1282"></a>
<span class="sourceLineNo">1283</span>                        }<a name="line.1283"></a>
<span class="sourceLineNo">1284</span>                    }<a name="line.1284"></a>
<span class="sourceLineNo">1285</span>                }<a name="line.1285"></a>
<span class="sourceLineNo">1286</span>            }<a name="line.1286"></a>
<span class="sourceLineNo">1287</span>        }<a name="line.1287"></a>
<span class="sourceLineNo">1288</span><a name="line.1288"></a>
<span class="sourceLineNo">1289</span>        if (!allowFlawedDiscovery) {<a name="line.1289"></a>
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<span class="sourceLineNo">1292</span>    }<a name="line.1292"></a>
<span class="sourceLineNo">1293</span><a name="line.1293"></a>
<span class="sourceLineNo">1294</span>    /**<a name="line.1294"></a>
<span class="sourceLineNo">1295</span>     * Report a problem loading the log adapter, then either return<a name="line.1295"></a>
<span class="sourceLineNo">1296</span>     * (if the situation is considered recoverable) or throw a<a name="line.1296"></a>
<span class="sourceLineNo">1297</span>     * LogConfigurationException.<a name="line.1297"></a>
<span class="sourceLineNo">1298</span>     * &lt;p&gt;<a name="line.1298"></a>
<span class="sourceLineNo">1299</span>     * There are two possible reasons why we successfully loaded the<a name="line.1299"></a>
<span class="sourceLineNo">1300</span>     * specified log adapter class then failed to cast it to a Log object:<a name="line.1300"></a>
<span class="sourceLineNo">1301</span>     * &lt;ol&gt;<a name="line.1301"></a>
<span class="sourceLineNo">1302</span>     * &lt;li&gt;the specific class just doesn't implement the Log interface<a name="line.1302"></a>
<span class="sourceLineNo">1303</span>     *     (user screwed up), or<a name="line.1303"></a>
<span class="sourceLineNo">1304</span>     * &lt;li&gt; the specified class has bound to a Log class loaded by some other<a name="line.1304"></a>
<span class="sourceLineNo">1305</span>     *      classloader; Log@classloaderX cannot be cast to Log@classloaderY.<a name="line.1305"></a>
<span class="sourceLineNo">1306</span>     * &lt;/ol&gt;<a name="line.1306"></a>
<span class="sourceLineNo">1307</span>     * &lt;p&gt;<a name="line.1307"></a>
<span class="sourceLineNo">1308</span>     * Here we try to figure out which case has occurred so we can give the<a name="line.1308"></a>
<span class="sourceLineNo">1309</span>     * user some reasonable feedback.<a name="line.1309"></a>
<span class="sourceLineNo">1310</span>     *<a name="line.1310"></a>
<span class="sourceLineNo">1311</span>     * @param badClassLoader is the classloader we loaded the problem class from,<a name="line.1311"></a>
<span class="sourceLineNo">1312</span>     * ie it is equivalent to badClass.getClassLoader().<a name="line.1312"></a>
<span class="sourceLineNo">1313</span>     *<a name="line.1313"></a>
<span class="sourceLineNo">1314</span>     * @param badClass is a Class object with the desired name, but which<a name="line.1314"></a>
<span class="sourceLineNo">1315</span>     * does not implement Log correctly.<a name="line.1315"></a>
<span class="sourceLineNo">1316</span>     *<a name="line.1316"></a>
<span class="sourceLineNo">1317</span>     * @throws LogConfigurationException when the situation<a name="line.1317"></a>
<span class="sourceLineNo">1318</span>     * should not be recovered from.<a name="line.1318"></a>
<span class="sourceLineNo">1319</span>     */<a name="line.1319"></a>
<span class="sourceLineNo">1320</span>    private void handleFlawedHierarchy(ClassLoader badClassLoader, Class badClass)<a name="line.1320"></a>
<span class="sourceLineNo">1321</span>        throws LogConfigurationException {<a name="line.1321"></a>
<span class="sourceLineNo">1322</span><a name="line.1322"></a>
<span class="sourceLineNo">1323</span>        boolean implementsLog = false;<a name="line.1323"></a>
<span class="sourceLineNo">1324</span>        String logInterfaceName = Log.class.getName();<a name="line.1324"></a>
<span class="sourceLineNo">1325</span>        Class interfaces[] = badClass.getInterfaces();<a name="line.1325"></a>
<span class="sourceLineNo">1326</span>        for (int i = 0; i &lt; interfaces.length; i++) {<a name="line.1326"></a>
<span class="sourceLineNo">1327</span>            if (logInterfaceName.equals(interfaces[i].getName())) {<a name="line.1327"></a>
<span class="sourceLineNo">1328</span>                implementsLog = true;<a name="line.1328"></a>
<span class="sourceLineNo">1329</span>                break;<a name="line.1329"></a>
<span class="sourceLineNo">1330</span>            }<a name="line.1330"></a>
<span class="sourceLineNo">1331</span>        }<a name="line.1331"></a>
<span class="sourceLineNo">1332</span><a name="line.1332"></a>
<span class="sourceLineNo">1333</span>        if (implementsLog) {<a name="line.1333"></a>
<span class="sourceLineNo">1334</span>            // the class does implement an interface called Log, but<a name="line.1334"></a>
<span class="sourceLineNo">1335</span>            // it is in the wrong classloader<a name="line.1335"></a>
<span class="sourceLineNo">1336</span>            if (isDiagnosticsEnabled()) {<a name="line.1336"></a>
<span class="sourceLineNo">1337</span>                try {<a name="line.1337"></a>
<span class="sourceLineNo">1338</span>                    ClassLoader logInterfaceClassLoader = getClassLoader(Log.class);<a name="line.1338"></a>
<span class="sourceLineNo">1339</span>                    logDiagnostic("Class '" + badClass.getName() + "' was found in classloader " +<a name="line.1339"></a>
<span class="sourceLineNo">1340</span>                                  objectId(badClassLoader) + ". It is bound to a Log interface which is not" +<a name="line.1340"></a>
<span class="sourceLineNo">1341</span>                                  " the one loaded from classloader " + objectId(logInterfaceClassLoader));<a name="line.1341"></a>
<span class="sourceLineNo">1342</span>                } catch (Throwable t) {<a name="line.1342"></a>
<span class="sourceLineNo">1343</span>                    handleThrowable(t); // may re-throw t<a name="line.1343"></a>
<span class="sourceLineNo">1344</span>                    logDiagnostic("Error while trying to output diagnostics about" + " bad class '" + badClass + "'");<a name="line.1344"></a>
<span class="sourceLineNo">1345</span>                }<a name="line.1345"></a>
<span class="sourceLineNo">1346</span>            }<a name="line.1346"></a>
<span class="sourceLineNo">1347</span><a name="line.1347"></a>
<span class="sourceLineNo">1348</span>            if (!allowFlawedHierarchy) {<a name="line.1348"></a>
<span class="sourceLineNo">1349</span>                StringBuffer msg = new StringBuffer();<a name="line.1349"></a>
<span class="sourceLineNo">1350</span>                msg.append("Terminating logging for this context ");<a name="line.1350"></a>
<span class="sourceLineNo">1351</span>                msg.append("due to bad log hierarchy. ");<a name="line.1351"></a>
<span class="sourceLineNo">1352</span>                msg.append("You have more than one version of '");<a name="line.1352"></a>
<span class="sourceLineNo">1353</span>                msg.append(Log.class.getName());<a name="line.1353"></a>
<span class="sourceLineNo">1354</span>                msg.append("' visible.");<a name="line.1354"></a>
<span class="sourceLineNo">1355</span>                if (isDiagnosticsEnabled()) {<a name="line.1355"></a>
<span class="sourceLineNo">1356</span>                    logDiagnostic(msg.toString());<a name="line.1356"></a>
<span class="sourceLineNo">1357</span>                }<a name="line.1357"></a>
<span class="sourceLineNo">1358</span>                throw new LogConfigurationException(msg.toString());<a name="line.1358"></a>
<span class="sourceLineNo">1359</span>            }<a name="line.1359"></a>
<span class="sourceLineNo">1360</span><a name="line.1360"></a>
<span class="sourceLineNo">1361</span>            if (isDiagnosticsEnabled()) {<a name="line.1361"></a>
<span class="sourceLineNo">1362</span>                StringBuffer msg = new StringBuffer();<a name="line.1362"></a>
<span class="sourceLineNo">1363</span>                msg.append("Warning: bad log hierarchy. ");<a name="line.1363"></a>
<span class="sourceLineNo">1364</span>                msg.append("You have more than one version of '");<a name="line.1364"></a>
<span class="sourceLineNo">1365</span>                msg.append(Log.class.getName());<a name="line.1365"></a>
<span class="sourceLineNo">1366</span>                msg.append("' visible.");<a name="line.1366"></a>
<span class="sourceLineNo">1367</span>                logDiagnostic(msg.toString());<a name="line.1367"></a>
<span class="sourceLineNo">1368</span>            }<a name="line.1368"></a>
<span class="sourceLineNo">1369</span>        } else {<a name="line.1369"></a>
<span class="sourceLineNo">1370</span>            // this is just a bad adapter class<a name="line.1370"></a>
<span class="sourceLineNo">1371</span>            if (!allowFlawedDiscovery) {<a name="line.1371"></a>
<span class="sourceLineNo">1372</span>                StringBuffer msg = new StringBuffer();<a name="line.1372"></a>
<span class="sourceLineNo">1373</span>                msg.append("Terminating logging for this context. ");<a name="line.1373"></a>
<span class="sourceLineNo">1374</span>                msg.append("Log class '");<a name="line.1374"></a>
<span class="sourceLineNo">1375</span>                msg.append(badClass.getName());<a name="line.1375"></a>
<span class="sourceLineNo">1376</span>                msg.append("' does not implement the Log interface.");<a name="line.1376"></a>
<span class="sourceLineNo">1377</span>                if (isDiagnosticsEnabled()) {<a name="line.1377"></a>
<span class="sourceLineNo">1378</span>                    logDiagnostic(msg.toString());<a name="line.1378"></a>
<span class="sourceLineNo">1379</span>                }<a name="line.1379"></a>
<span class="sourceLineNo">1380</span><a name="line.1380"></a>
<span class="sourceLineNo">1381</span>                throw new LogConfigurationException(msg.toString());<a name="line.1381"></a>
<span class="sourceLineNo">1382</span>            }<a name="line.1382"></a>
<span class="sourceLineNo">1383</span><a name="line.1383"></a>
<span class="sourceLineNo">1384</span>            if (isDiagnosticsEnabled()) {<a name="line.1384"></a>
<span class="sourceLineNo">1385</span>                StringBuffer msg = new StringBuffer();<a name="line.1385"></a>
<span class="sourceLineNo">1386</span>                msg.append("[WARNING] Log class '");<a name="line.1386"></a>
<span class="sourceLineNo">1387</span>                msg.append(badClass.getName());<a name="line.1387"></a>
<span class="sourceLineNo">1388</span>                msg.append("' does not implement the Log interface.");<a name="line.1388"></a>
<span class="sourceLineNo">1389</span>                logDiagnostic(msg.toString());<a name="line.1389"></a>
<span class="sourceLineNo">1390</span>            }<a name="line.1390"></a>
<span class="sourceLineNo">1391</span>        }<a name="line.1391"></a>
<span class="sourceLineNo">1392</span>    }<a name="line.1392"></a>
<span class="sourceLineNo">1393</span>}<a name="line.1393"></a>




























































</pre>
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